Track Telegram avatar changes in telegram backend state DB

telegram_backend/src/profile-state.ts

@@ -0,0 +1,113 @@
+import { mkdirSync } from "node:fs";
+import path from "node:path";
+import Database from "better-sqlite3";
+import type { OmniInboundEnvelopeV1 } from "./types";
+
+const TELEGRAM_FILE_MARKER = "tg-file:";
+const DEFAULT_STATE_DB_PATH = path.join(process.cwd(), ".data", "telegram_backend", "state.sqlite");
+
+type AvatarStateRow = {
+  avatarFingerprint: string | null;
+};
+
+function asString(value: unknown) {
+  if (typeof value !== "string") return null;
+  const normalized = value.trim();
+  return normalized || null;
+}
+
+function stateDbPath() {
+  const fromEnv = asString(process.env.TELEGRAM_PROFILE_STATE_DB_PATH);
+  return fromEnv ?? DEFAULT_STATE_DB_PATH;
+}
+
+function parseTelegramFileId(avatarUrl: string | null) {
+  const raw = asString(avatarUrl);
+  if (!raw || !raw.startsWith(TELEGRAM_FILE_MARKER)) return null;
+  const fileId = raw.slice(TELEGRAM_FILE_MARKER.length).trim();
+  return fileId || null;
+}
+
+function openStateDb() {
+  const dbPath = stateDbPath();
+  const dbDir = path.dirname(dbPath);
+  mkdirSync(dbDir, { recursive: true });
+
+  const db = new Database(dbPath);
+  db.exec(`
+    CREATE TABLE IF NOT EXISTS telegram_contact_profile_state (
+      contact_external_id TEXT PRIMARY KEY,
+      avatar_fingerprint TEXT,
+      avatar_file_id TEXT,
+      updated_at TEXT NOT NULL
+    )
+  `);
+  return db;
+}
+
+const db = openStateDb();
+const selectStateStatement = db.prepare(`
+  SELECT avatar_fingerprint AS avatarFingerprint
+  FROM telegram_contact_profile_state
+  WHERE contact_external_id = ?
+`);
+const upsertStateStatement = db.prepare(`
+  INSERT INTO telegram_contact_profile_state (
+    contact_external_id,
+    avatar_fingerprint,
+    avatar_file_id,
+    updated_at
+  )
+  VALUES (?, ?, ?, ?)
+  ON CONFLICT(contact_external_id) DO UPDATE SET
+    avatar_fingerprint = excluded.avatar_fingerprint,
+    avatar_file_id = excluded.avatar_file_id,
+    updated_at = excluded.updated_at
+`);
+
+function detectAvatarChange(input: {
+  contactExternalId: string | null;
+  avatarFileId: string | null;
+  avatarFingerprint: string | null;
+}) {
+  const contactExternalId = asString(input.contactExternalId);
+  const avatarFileId = asString(input.avatarFileId);
+  const avatarFingerprint = asString(input.avatarFingerprint) ?? avatarFileId;
+
+  if (!contactExternalId || !avatarFileId || !avatarFingerprint) {
+    return { changed: false };
+  }
+
+  const row = selectStateStatement.get(contactExternalId) as AvatarStateRow | undefined;
+  const previousFingerprint = asString(row?.avatarFingerprint);
+  const changed = previousFingerprint !== avatarFingerprint;
+
+  if (changed) {
+    upsertStateStatement.run(contactExternalId, avatarFingerprint, avatarFileId, new Date().toISOString());
+  }
+
+  return { changed };
+}
+
+export function applyAvatarProfileState(envelope: OmniInboundEnvelopeV1): OmniInboundEnvelopeV1 {
+  const payload = envelope.payloadNormalized;
+  const contactExternalId = asString(payload.contactExternalId);
+  const contactAvatarUrl = asString(payload.contactAvatarUrl);
+  const contactAvatarFingerprint = asString(payload.contactAvatarFingerprint);
+  const avatarFileId = parseTelegramFileId(contactAvatarUrl);
+
+  const avatarState = detectAvatarChange({
+    contactExternalId,
+    avatarFileId,
+    avatarFingerprint: contactAvatarFingerprint,
+  });
+
+  return {
+    ...envelope,
+    payloadNormalized: {
+      ...payload,
+      contactAvatarChanged: avatarState.changed,
+      contactAvatarUrl: avatarState.changed ? contactAvatarUrl : null,
+    },
+  };
+}